The present invention relates to the manufacturing engineering of a semiconductor device, particularly relates to a bonding technique for bonding an inner lead laid on a carrier to an electrode pad formed on a semiconductor chip (hereinafter called chip) and, for example, relates to a bonding technique effective when utilized for a method of manufacturing a semiconductor integrated circuit (hereinafter called IC) provided with a chip-sized package or a chip scale package (hereinafter called CSP) in size equal to or approximately equal to the size of a chip.
As electronic equipment using ICs are miniaturized and thinned, the reduction of an IC package is desired. Various CSPs are developed to meet the above demand and, a micro ball grid array package (hereinafter called ).LBGA) constituted as follows is one example. That is, a tape carrier is mechanically connected on the main surface on the side of an electrode pad of a chip via an insulating film, each inner lead laid on the tape carrier is bonded to each electrode pad of the chip and a bump as each external terminal is soldered to each outer lead and protruded.
For a method of bonding an inner lead in μBGA, there is a single point bonding method (hereinafter called only bonding method) of successively welding multiple inner leads one at a time on each electrode pad arranged on the overall chip with pressure by a bonding tool.
CSP is described on pages 112 and 113 of a monthly, “Semiconductor World” published in May, 1995 by Press Journal.
For an example describing a method of bonding a memory chip to a TAB package in which when a memory chip is mounted in a tape automated bonding (TAB) type package according to a lead on chip method based upon a film carrier, no deterioration in the strength of bonding caused by the dislocation of bonding occurs, further forming of a metallic mold and others are not required and the cost is low, there is Japanese Patent Application Laid-Open No. Hei 6-13428. In the above bonding method, after an inner lead is bend and transformed by a bonding tool before bonding, the inner lead is pressurized by the bonding tool and bonded to an electrode pad of a chip.